In this study, Na-montmorillonite was organically modified with cetyltrimethylammoniumbromide (CTAB) and intercalated with in-situ polymerized indene. Polyindene(PIn)/Organo-MMT nanocomposites were obtained with three different compositions and coded as: K1: [PIn(94.5%)/O-MMT(5.5%)], K2: [PIn(92.8%)/ O-MMT(7.2%)], and K3: [PIn(87.9%)/O-MMT(12.1%)].These nanocomposites were subjected to full characterization with various techniques. Electrokinetic studies were conducted to reveal the zeta (f)-potential characteristics of the nanocomposites. f-potentials of the materials were observed to decrease with increasing O-MMT content. The cationic (CTAB) and anionic (sodium dodecylsulfate) surfactants were shifted the f-potentials of the colloidal dispersions to more positive and more negative regions, respectively whereas nonionic surfactant (Triton X-100) caused almost no change. The pH and temperature were observed to shift the f-potential values of the nanocomposites to more negative and slightly more positive regions, respectively. With the addition of mono (NaCl), di (BaCl 2 ) and three (AlCl 3 ) valent salts, the f-potential of the nanocomposites were shifted to more negative, more positive, and much more positive regions, respectively.

In this study, polyindene (PIn) and three PIn/organo-montmorillonite (O-MMT) nanocomposites namely K1: [PIn(94.5%)/O-MMT(5.5%)], K2: [PIn(92.8%)/ O-MMT(7.2%)], and K3: [PIn(87.9%)/O-MMT(12.1%)] were used to investigate the electrorheological (ER), creep-recovery, and vibration damping characteristics. A volume fraction series (u ¼ 5-25%) of suspensions were prepared from the samples in silicone oil (SO). First, zeta (f)-potentials and antisedimentation stabilities; second, ER properties of these nanocomposite/SO suspension systems were determined under externally applied electric field strengths. Besides, the effects of dispersed phase volume fraction, shear rate, electric field strength, and temperature onto ER performance of these suspensions were investigated and non-Newtonian rheological behaviors were observed. The vibration damping capabilities of the suspensions were investigated using various rheological parameters on the electrorheometer and on an automobile shock absorber and a 66% vibration damping capacity were determined under an applied electric field strength, which is an important property from industrial point of view. Furthermore, the materials were subjected to creep and creeprecovery tests and reversible viscoelastic deformations were determined. From the experiments carried out, the nanocomposites were classified as smart materials.

BackgroundTakayasu arteritis (TA) is characterised by inflammation of large arteries causing stenosis, occlusion, dilatation and/or aneurysm of affected vessels. TA is most commonly seen in younger women between 20–30 ages. Etiopathogenesis of TA is largely unknown although evidence suggest complex interplay between environmental and genetic factors such as HLA (human leukocyte antigen) groups. The coexistence of TA with spondyloarthropathies (SPA) has been reported in limited case series, raising hypotheses about shared pathogenetic mechanisms.ObjectivesTo determine prevalence of spondyloarthropathy in patients with TA.MethodsDetailed clinical and demographic features of TA patients were recorded and all were screened for the presence of SPA following recommendations of (ASAS). Patients were questioned for inflammatory back pain, enthesitis, uveitis, inflammatory bowel disease, peripheral arthritis, and investigated accordingly with HLA-B27, plain X-rays of pelvis and sacroiliac magnetic resonance imaging. Radiographic spondyloarthritis was reported in case of bilateral grade ≥2 or unilateral grade ≥3 sacroiliitis.ResultsThere were 65 patients (61 female, 4 male) in the cohort. Mean age was 43±13 years and age at the diagnosis of TA was 35±13 years. Inflammatory bowel disease, psoriasis and psoriatic arthritis were observed in four, three and one patients. Chronic axial pain was reported by 26 (40%) patients but inflammatory back pain was evident in 13 (20%) patients. Chronic arthritis was observed in 4 patients. HLA-B27 was positive in three patients. Six patients were diagnosed as radiographic SPA and 3 were diagnosed as non-radiographic SPA. In sum nine patients were diagnosed as SPA (14.2%).ConclusionsOur study demonstrated that SPA is common in patients with Takayasu arteritis suggesting shared pathogenetic mechanisms.Disclosure of InterestNone declared